Tobacco use is the leading preventable cause of death in the United States and throughout much of the world. Public health efforts over the last 50 years have dramatically decreased the prevalence of smoking, leading to a marked decrease in morbidity and mortality. Further efforts in tobacco control are needed though to help prevent the approximately 430,000 annual tobacco-related deaths in the US. This K24 midcareer award will allow me to improve the quantity and quality of mentoring I provide to junior faculty. My research focus for this award will be on understanding waterpipe tobacco use from a behavioral economics perspective. This discipline is an effort to reunite the fields of psychology and economics to better understand human behavior, and it has recently been applied to helping understand cigarette use. For this K24 award, I would increase my knowledge in behavioral economics and use this framework to evaluate waterpipe tobacco use. My goals for this K24 are: Career goal 1. To mentor additional junior faculty in patient-oriented research on substance use disorders, primarily focused on tobacco control Career goal 2. To evaluate the quality of my mentoring and develop a plan for improvement. Career goal 3. To increase my expertise at the behavioral, economic and policy aspects of alternate tobacco products, primarily focusing on water pipe (hookah) tobacco use. I am proposing three sequential small studies that will help increase my expertise in the behavioral economic aspects of waterpipe tobacco use and provide additional data to share with trainees, both of which will help me in mentoring junior faculty. My specific research aims: Research Aim 1. To understand the business and financial aspects of waterpipe tobacco smoking, as well as to understand the knowledge, attitudes and beliefs of hookah bar owners. Research Aim 2. To understand the knowledge, attitudes and beliefs and financial preferences of waterpipe tobacco users. Research Aim 3. To develop preliminary models of the cost-effectiveness of a cessation intervention for waterpipe tobacco use and of the effect of different financial regulatory approaches to waterpipe tobacco use.